stress fracture in tibia not healing

In November of 2008 I was diagnosed with a stress fracture in my left tibia. I am about 20 pounds overweight and jumped into basketball too quickly (that is where the fracture took place). I was went to the Ortho and had an x-ray done, he then did a test by running his finger up and down my bone and explained that I had a stress fracture after I jumped back in pain when he went over a small area of my left shin. I wore a boot for about two months. I went back in for a follow up and I was still in pain. The x-ray did not show the stress fracture anymore, but the pain was coming and going (based on walking and some light activity with the kids), it was concentrated on that one spot the doctor had found and still is to this day. I am 35 years old as of last Sunday, so I was 34 when this took place. I rested and did not play basketball for the entire spring and summer.
I did continue to play golf and ride in a cart once my boot was off. My leg still feels pain when I have any impact on it or I bump it, and I cannot play basketball to this day. It has been almost 12 months and I am so frustrated and do not know where to turn for a recovery plan. My doctor has offered no real solution. He did do a bone scan which did not show up the fracture, only some shin splint. I later came to learn from a friend that is a doctor that it is very hard to find that fracture with a bone scan.
I am at the end of my rope and must start being able to do some sort of exercise. Even riding a stationary bike causes pain to that leg, and it often delayed. Does anyone have any experience with this or has anyone had a long recovery from such an injury?
Thank you so much and if you have any questions please ask. :$ :'( :'(